[set fair (OP)]

Putting propylene glycol in hospital air conditioning was fairly common around the middle of the last century. It acted as a bactericide - presumed to dehydrate the bacteria, although I haven't found any reference to evidence that this was how it works.

Is it still used? With growing antibiotic resistance is it time to start using it again?

[chris]

I was not aware of this; do you have a reference?

Just speculating here, but hospital water supplies and aircon systems have come under a lot of scrutiny in recent years with respect to entities like Legionella; changes in policy and practice may well have come in the wake of this.

[Colin2B]

I have seen reference to it being used in air conditioning systems as an antifreeze where ethylene glycol is considered too dangerous to use in case of leak eg food processing/storage. Never come across it being put into the air itself.

[set fair (OP)]

I was not aware of this; do you have a reference?

https://www.jpeds.com/article/S0022-3476(42)80046-3/abstract

[set fair (OP)]

try again https://www.jpeds.com/article/S0022-3476(42)80046-3/abstract

[RD]

... Never come across it being put into the air itself.

Apparently it's in e-cigs ... https://www.sciencedirect.com/science/article/pii/S0278691517305112

[and its (acidic) breakdown products will corrode metal (refrigeration) pipes].

[Colin2B]

Apparently it's in e-cigs ...

Yes, I found that a short while ago when looking to see if there were any side effects to inhaling the vapour. CDC has a whole paper on it.
Not sure I would want to inhale something that corrodes refrigeration pipes!

[Bored chemist]

Apparently it's in e-cigs ...

Yes, I found that a short while ago when looking to see if there were any side effects to inhaling the vapour. CDC has a whole paper on it.
Not sure I would want to inhale something that corrodes refrigeration pipes!

I'm OK with inhaling oxygen and water.

I wonder if glycol still gets used as an air conditioner or if it has been replaced by systems that rely on cooling to strip excess humidity.

[Colin2B]

I'm OK with inhaling oxygen and water.

Good point 
Still not keen on glycol

I wonder if glycol still gets used as an air conditioner or if it has been replaced by systems that rely on cooling to strip excess humidity.

I thought it’s main use was in the air conditioning cooling water as an antifreeze, rather than as an ‘air conditioner’.